Were is doofs headquarters in the game 2demision yourself?

In the game "Phineas and Ferb: Across the 2nd Dimension", Doofenshmirtz's headquarters is located in an alternate dimension known as the "2nd Dimension". It is a large, futuristic building located in a desert-like landscape. The headquarters is equipped with various machines and devices that Doofenshmirtz uses to create his evil plans.